perioperative...perioperative ultrasonography ehab farag, md, frca hesham elsharkawy ......
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Perioperative Ultrasonography
Ehab Farag, MD, FRCA
Hesham Elsharkawy
David G. Anthony, M.D.
Cleveland Clinic, Cleveland OH
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• Complications during central venous catheterization (CVC)
occur 2% -15% of the time in adults and can be severe1.
• Shummer et al.
– 1794 cases, critical-care physicians
– landmark techniques
– 3.3% complication rate (10 cases pneumothorax/hemothorax
and one stroke leading to death)
1Domino KB, et al. Anesthesiology 2004;100:1411-8.
2Shummer W, et al. Intensive Care Medicine 2004;33:1055-1059.
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• ASA closed claims 13 deaths from CVC insertion.
• Hemothorax from arterial injury & pneumothorax:
major contributors to mortality1.
• 5 million CVCs are performed every year2 even
low incidence (0.5%) of significant complications
would result in 25,000 problems.
1Bowdle TA. ASA Newsletter 2002;66.2Feller-Kopman. Crit Care Med 2005;33:1875-7.
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• The Agency for Healthcare Research and Quality
– US 1 of 11 practices to improve the patient safety and
outcome*.
• 2003, a meta-analysis by Hind, 18 RCTs
– favored US guidance vs landmark techniques
– reduced failure rates
– increased first-attempt success,
– reduced complication rates and faster procedure time
(P<0.0001)
*Rothschild JM. Agency for Healthcare Research and Quality 2001:2245-53.
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Subclavian Vein Approach
• SV offers ideal size for central access.
• Close proximity to the lung, subclavian artery, and
brachial plexus can lead to significant morbidity.
• Other challenges for accessing the SV with US are
deeper location and the presence of the clavicle.
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Femoral Vein Approach
• Baum et al reviewed 100 CT scans
– FV and the femoral artery overlap in the anteroposterior plane
65% of the time1.
• Same finding confirmed in US study in 50 ICU
patients2.
1Baum PA, et al. Radiology 1989;173:775-7.2Hughes P, et al. Anaesthesia 2000;55:1198-202.
TRANSTHORACIC
ECHOCARDIOGRAPHY
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Possibilites with Bedside Ultrasound
• Etiologies of Hemodynamic Decompensation
– Vasodilatory/Distributive Shock
– Cardiogenic Shock
– Heart Failure
– Regional wall motion abnormalities
• Monitor Resuscitation Efforts
Limited TTE Exam Types
• FATE (Focus Assessed Transthoracic Echocardiography),
• FEEL (Focused Echocardiographic Evaluation in Life Support)
• FEER (Focused Echocardiographic Evaluation in Resuscitation Management),
• RUSH (Rapid Ultrasound for Shock and Hypotension),
• CAUSE (Cardiac Arrest Ultrasound Exam)
• BLEEP (Bedside Limited Echocardiography by Emergency Physician)
Our Exam (FATE)
• Three Anatomic windows
• Four “clock positions:” 10:00, 2:00, 3:00 12:00
• Five scanning views
• In the ideal patient!
Proper probe grasp
X
Probe Orientation
Parasternal Long Axis View
• Parasternal Long
Axis
• Left Upper Sternal
Border (3rd-4th
interspace)
– Probe Indicator pointed
towards right shoulder
(10:00)
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Anatomic Correlate
Courtesy of Yale University Echocardiography Atlas
Parasternal Short Axis View
• Parasternal Short Axis
• Left Upper Sternal
Border (3rd-4th
interspace)
– Probe Indicator pointed
towards left shoulder
(2:00)
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Anatomic Correlate
Courtesy of Yale University Echocardiography Atlas
Apical View
• Point of Maximal
Impulse (PMI)
• Anterior Axillary Line
underneath breast
• Probe Orientation: 3:00
(patient’s left flank)
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Anatomic Correlate
Courtesy of Yale University Echocardiography Atlas
Subcostal View
• Probe in subxiphoid region
• Probe orientation: 3:00
• Tilt parallel to back
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Anatomic Correlate
Courtesy of Yale University Echocardiography Atlas
IVC View
• Probe in subxiphoid region
• Obtain the subcostal view,
then rotate the probe
• Probe orientation: 12:00
• Tilt towards the back
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Volume Responsiveness
• Collapsibility Index =
[IVC max (end exhalation) – IVC min (end inhalation)] x 100%
IVC max (end exhalation)
– > 50-75% or exhaled diameter < 1 cm suggestive of hypovolemia
• Distensibility Index =
[IVC max (end exhalation) – IVC min (end inhalation)] x 100%
IVC Mean
– > 12 % variation: volume responsiveness: 93% PPV; 92% NPV
GASTRIC, OPHTHALMIC, AND
PULMONARY ULTRASOUND
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Ultrasound for Gastric Content
Three outcomes should be assessed:
1-Identify if the stomach is empty or full
2-Identify if the contents is fluid or solid
3-Identify the volume of the content
3-Volume of the content (Quantitative)
• Mathematical models predict GV based on antralCSA.
• (GV (ml)=27.0+14.6×right-lateral CSA (cm2) −1.28×age (yr))
• Predict volume up to 500 ml.• Perlas A, Mitsakakis N, Liu L, et al. Validation of a mathematical model for ultrasound
assessment of gastric volume by gastroscopic examination. Anesth Analg 2013;116:357–63.
Disadvantages:
Not continuous
Cannot quantitate CSF pressure
Operator dependent
Not widely accepted.
Optic nerve sheath is a
continuation of duramater
ICP CSF
pressureONSD
Advantages:
ICP changes transmitted within minutes
Non-invasive
No reported complications
Optic nerve sheath Ultrasonography for
monitoring intra cranial pressure
Scan 1 : longitudinal B- Scan
FDA approved ultrasound probe and machine for ocular ultrasonography
Requirements:
• Mechanical index < 0.23
• Thermal index < 1.0
Scan 2 : transverse B- Scan
Scan 3 : transverse and confirmatory A- Scan
ONSD greater than 5.0 mm reliably predicts an ICP > 20
mm Hg
Sliding Sign
Normal Lung
Absence of lung-sliding
and Comet-tail is 96.5%
specific to pneumothorax.
B-lines’ or ‘comet-tail artifacts’
A-lines
Power slide
“stratosphere sign” or “barcode sign”
Absent lung sliding and Comet-tail
Pneumothorax
Diaphragmatic Motion
Neuromuscular Ultrasound for Evaluation of the Diaphragm, Aarti Sarwal et
al
Intercostal view
Anterior Subcostal View
TechniquePatientswere imaged using a Philips ATL Sono CT 5000using a 2–5M Hz curved linear transducer. Patientswere scanned supine; in the case of ventilated patientsit was necessary to briefly disconnect the ventilatorto assess the patients’ spontaneous respiratory efforts.The patients were asked to breathe comfortably andto sniff when requested. Patients were scanned inter-costally in the anterior axillary line with the probeangled cranially so as to have the diaphragm as closeaspossible to 90 degrees to theprobe. The liver wasusedas a window on the right while the spleen was used onthe left. The M mode line of sight was angled to obtainthe maximal diaphragmatic excursion. I f unilateralparalysis was suspected the normal side was scannedfirst. M mode was performed in conjunction withconventional brightness-mode (B mode) grey-scaleultrasound.
The M mode charts movement against time along theM mode line giving a linear analogue of the motion ofthe object being studied, in this case the diaphragm.Normal inspiratory diaphragmatic movement is caudal,with the corresponding M mode trace being upwards asthe diaphragm moves toward the probe, the expiratorytrace is downwards as the diaphragm moves away fromthe probe (ie cranially). The inspiratory phase ofrespiration is noted by a preceding pause in the tracenot present before the expiratory phase. The phase ofrespiration can also be noted and recorded by thesonographer. A normal sniff is demonstrated as a sharpupstroke on the screen, whereas a paralyzed diaphragmwill either demonstrate absent movement or paradoxical(ie cranial) movement.
For the purposes of our study only the direction ofdiaphragm excursion was noted, we did not takemeasurements of the range of excursion.
Results
The results are summarized in Table 1.Normal examination (Figures1 and 2): Threepatients
scanned demonstrated normal diaphragmatic move-
Table 1 Summary of details and findings on all subjects
Subject SexAge
( years) Reason for suspicion Chest X-ray findings Findings with M mode US
1 M 26 C6 fracture tetraplegia High L hemi-diaphragm onCXR
L diaphragmatic paralysis
2 M 61 Dyspnoea when swimming orstanding in deep water
High R diaphragm on CXR R diaphragmatic paralysis
3 M 16 C5 incomplete tetraplegia No CXR abnormalities No abnormality seen4 M 31 C4 incomplete tetraplegia No CXR abnormalities No abnormality seen5 F 23 Disseminated
encephalomyelitisNo CXR abnormalities R diaphragmatic paralysis
6 M 51 M ixed connective tissuedisease, loss of lung volume,paradoxical respiratorymovements
Both diaphragms raised onCXR
Normal diaphragmaticmovement bilaterally
7 M 29 Attempted suicide by hanging,incomplete C3 tetraplegia
Raised R hemi-diaphragm onCXR
R diaphragmatic palsy
8 M 18 Complete C2 tetraplegia,pushbike accident
No CXR abnormalities(ventilated)
L diaphragmatic palsy. Secondscan done due to increasingtime off ventilator noimprovement
9 M 28 Complete C2 tetraplegia,ventilator dependant
No CXR abnormalities(ventilated)
Bilateral palsy withparadoxical movement
10 M 17 M ulti trauma, R brachialplexus injury
Raised R diaphragm on CXR R diaphragmatic palsy withparadoxical movement
Figure 1 M mode ultrasound trace of normal diaphragmmovement. Normal trace of diaphragmatic movement. Ininspiration, movement is caudal, with the corresponding Mmode trace being upwards as the diaphragm moves toward theprobe. In expiration, the M mode trace is downwards as thediaphragm moves away from the probe
Diaphragmatic paralysis
TLloyd et al
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Spinal Cord
ment. The M mode trace demonstrated caudal move-ment of the diaphragm bilateral ly (towards the topof the screen) and a sharp upstroke on the sniff test.
Diaphragmatic paralysis (Figures 3 and 4): Sixpatients were found to have evidence of a unilateraldiaphragmatic paralysis. This wasowing to high cervicalspine injury (n¼3), brachial plexus injury (n¼1)disseminated encephalomyelitis (n¼1) and idiopathic(n¼1). Four of these patients were noted to have araised hemi-diaphragm on CXR. Of the two who didnot have a raised hemi-diaphragm on CXR, one waspermanently ventilated.
M mode tracing of movement on the normal sidedemonstrated caudal movement with inspiration anda sharp upstroke on the sniff test. The M mode trace
of theparalyzed sideshowed no activecaudal movementof the diaphragm with inspiration and paradoxicalmovement (ie cranial movement on inspiration) parti-cularly with the sniff test. No measurements ofdiaphragmatic excursion were taken.
One patient had evidence of bilateral diaphragmaticparalysis. This patient’s M mode trace showed para-doxical movement bilateral ly with inspiratory effort.His chest X-ray did not show raised diaphragms, thoughit should be noted that he was permanently ventilated.
The sensitivity of Chest X-ray was 66.6% forunilateral paralysis and 57% for paralysis in general.
Discussion
The diaphragm is the principal muscle of respiration.In concert with the other accessory muscles of respira-tion it enlarges the chest cavity on inspiration, allowingthe lung to passively inflate owing to the negativeintra-thoracic pressure. When the diaphragm relaxes,the intrathoracic pressure rises, and air is forced outof the chest. I f one or both of the hemi-diaphragmsis paralyzed, the negative pressure created at inspirationby the other muscles of respiration causes the dia-phragm to passively move cranially, as opposed to itsnormal active caudal movement. M ethods of evaluationof the suspected paralyzed diaphragm focus on eitherobserving the direction of movement or measuring thepressure in the chest.
Fluoroscopy has traditionally been the modality ofchoice for imaging of the suspected paralyzed dia-phragm (the default gold standard). Houston et al,5
however, noted a number of limitations to this modality;it requires patient cooperation and the ability of thepatient to maintain themselves upright, involvesa significant radiation dose and is a subjective method,with results difficult to reproduce. Some of thetechniques that a patient uses to compensate for
Figure 2 M mode ultrasound trace of normal diaphragmmovement. In a normal diaphragm a sharp upstroke isdemonstrated when the patient sniffs
Figure 3 M mode ultrasound trace of paralyzed diaphragm.A paralysed diaphragm demonstrates absent movement withrespiration
Figure 4 M mode ultrasound trace of paralyzed diaphragm.In a paralysed diaphragm, there is paradoxical (ie cranial) orabsent movement when the patient sniffs
Diaphragmatic paralysis
T Lloyd et al
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Spinal Cord
Subxiphoid view
Posterior subcostal view